Metering malfunctions

I switched to essential 10 last night about 10:00pm with 2.1 GB left and it converted it to 2.1GB on my new plan and I double checked my data and plan a few minutes later and it switched but it said 3.8 GB used...And the next morning I was supposed to have free zone till 8:00am and I only used it from 5:00am to 8:00 am and the meter went to 4.7 GB used....I am being over metered!!! Please fix this for me please....Tony....Thankyou for your attention..